1. Field of the Invention
The present invention relates to a version management apparatus and method, which manage the versions of data having link structure that can be obtained by designating addresses.
2. Discussion of the Background
In general, since data are updated or deleted after they are created, version management for storing data of the previous version and searching it later or comparing it with data of a new version has been necessary. In a conventional version management tool, individual data to be managed must be designated in advance.
When the number of data is large, such data are distributed via a network, or a plurality of persons add, delete, and update data, it becomes hard to recognize the states of the individual data. Consequently, it becomes hard to designate the individual data to be managed, thus disabling version management. In particular, in version management of data having link structure, only a version management tool that manages data having link structure in the same manner as normal data is available, and no tool can manage versions by utilizing the features of the data having link structure.
On the other hand, in order to search only required data from a large number of data, it is effective to perform search for all the data. For large-scale data having link structure, for example, a search service for hypermedia data on WWW (World Wide Web) on the Internet is already available. However, such search service concerns only data of relatively new unique version, and no search service that also concerns previous versions is available.
In this manner, even when version management of data having link structure is done, individual data must be designated, and version management is often difficult when the number of data is large.
Also, upon search of data having link structure, data of the previous version cannot be searched.